The present invention relates to an automated data storage system having one or a plurality of data accessors, and an apparatus and a method to remove one of those data accessors from the automated data storage system.
Automated data storage libraries are known for providing cost effective access to large quantities of stored data. Generally, data storage libraries include a large number of storage slots on which are stored portable data storage media. The typical portable data storage media is a tape cartridge, an optical cartridge, a disk cartridge, and the like. One (or more) accessor typically accesses the data storage media from the storage slots and delivers the accessed media to a data storage drive for reading and/or writing data on the accessed media. Suitable electronics both operate the accessor and operate the data storage drives to transmit and/or receive data from an attached on-line host computer system.
In a conventional automated data storage library, the storage slots are arranged in a planar orthogonal arrangement forming a xe2x80x9cwallxe2x80x9d of storage slots for holding data storage media. The plane may be a flat plane, or may be a cylindrical plane. To double the storage capacity, two xe2x80x9cwallsxe2x80x9d of storage slots may be provided on either side of the accessor.
A number of different companies manufacture automated data storage libraries today, each model displaying various different features. One example is the IBM 3494 Data Storage Library. Some of the automated data storage libraries have dual or multiple accessors to provide a level of redundancy, in that, one accessor is the xe2x80x9cactivexe2x80x9d accessor and the other may take over the accessor function and be the active accessor.
In many conventional libraries, one of the accessors is always the active accessor, and the other(s) is always spare. For example, in a dual accessor automated data storage library, the active accessor conducts all of the operations to access and move the data storage media, and the other accessor is the spare and is moved out of the active operation area. In other conventional libraries, multiple accessors may share the active operation and no accessors are spare. Occasionally, an accessor may become unavailable, for example, if a component of the accessor must be replaced or repaired.
Applicants"" invention includes a maintenance robot which can remove from Applicants"" automated data storage system an accessor having an attachment slot(s) and retractable wheels. Applicants"" maintenance robot includes a frame having a first support member pivotally connected thereto, a plurality of wheels rotatably mounted on said frame, and an attachment device mounted on the first support member. The attachment device is formed such that it can be inserted into, and subsequently removed from the attachment slot(s)located on the accessor. In one embodiment, the attachment device can be raised or lowered.
Applicants"" invention also includes an automated data storage system. Applicants"" automated data storage system includes at least one data storage library which includes a plurality of data storage media stored in a plurality of storage slots and at least one data storage drive for receiving said data storage media and reading and/or writing data thereon. Applicants"" automated data storage system further includes a first rail system located within the data storage library, and one or a plurality of accessors for accessing and transporting the stored media between the individual storage slots and the data storage drive. Each these accessors includes a plurality of retractable wheels and an attachment slot(s). Each of these data accessors are moveably disposed on the first rail system.
Applicants"" automated data storage system further includes a second rail system having a first end and a second end, with the first end located adjacent the first rail system. Applicants"" maintenance robot is movably disposed on the second rail system.
Applicants"" invention further includes a method to remove an accessor from Applicants"" automated data storage system. Applicants"" method includes the steps of: (i) positioning accessor on the first rail system adjacent the first end of the second rail system, (ii) positioning the maintenance robot on the second rail system adjacent the accessor, (iii) attaching the accessor to the maintenance robot, (iv) retracting the accessor""s wheels, and (v) removing the maintenance robot and the attached accessor from the data storage library. In a separate embodiment, Applicants"" method also includes a step wherein the maintenance robot lifts/lowers the attached accessor to completely remove that accessor from the first rail system.